I am sorry but this doesn't make sense. Chromium is an open source software and in no way is glued together with any operating system. Unless you want to glue it. They can just have edge WebView2... glued with the os the same way google has to use android webview when a webview is needed.
Microsoft back in the days was forced to... unglue... Internet Explorer. And they managed to do it in a browser that was.. glued in the first place. No OS has to glue anything no matter the source of it being open or closed. Unless they want to glue.
Microsoft btw just.. managed to unglue... Teams from Office... this is way more difficult to do. They will find a way to unglue Edge lol.